T24212 cros-build: add commands to bootstrap.sh
Add commands to either enter the CrOS SDK chroot or open a shell in the container, interactively or with some arbitrary commands.
For example, this makes it possible to call the bootstrap.sh script and invoke a build script in the chroot to set everything up and build a firmware image all in one go.
Signed-off-by: Guillaume Tucker guillaume.tucker@collabora.com